Gauff had to overcome 23 double-faults to win for the first time since the French Open final, outlasting fellow American Danielle Collins 7-5, 4-6, 7-6 (2) in the second round of the National Bank Open.

Gauff's serve changes are still embedding into her tennis. But she has other ways to win when the double faults start.

After surviving a 23-double fault showing two days prior, Coco Gauff overcame another 14 in her win over Veronika Kudermetova to reach the Round of 16 in the National Bank Open.